Apparatus for crimping yarn



April 30, 1957 2,790,298

A. KUNZLE APPARATUS FOR CRIMPING YARN 6 Sheets-Sheet 1 Filed March 11,1954 INVENTOR.

AUGUST [fix/V2145. v

I 30, 1957 A. KUNZLE 2,790,298

' APPARATUS FOR CRIMPING YARN .Filed March 11, 1954 6 Sheets-Sheet 2 ENTOR.

A us'usr Kuzvzz. E. BY

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April 30, 1957 v A. KUNZLE 2,790,293

APPARATUS FOR CRIMPING- YARN Filed March 11, 1954 6 Sheets-Sheet 3 r 3 Ig INVENTOR.

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BY W, M, 2%,M

A, KUNZLE APPARATUS FQR CRIMPING YARN April 30, 1957 6 Sheets-Sheet 5Filed March 11. 1954 INVENTOR. A uau: rid/-21. E.

BY yum WQLW nited States Patent APPARATUS FOR CRIMPING YARN AugustKnnzle, Wattwil, Switzerland, assignor to Heberlein Patent Corporation,New York, N. Y., a corporation of New York Application March 11, 1954,Serial No. 415,491

Claims priority, application Austria March 25, 1953 Claims; (Cl. 57-34)This invention relates to apparatus for crimping yarn and moreespecially for permanently crimping synthetic linear organic polymeryarn by false twisting.

It has been heretofore proposed to provide apparatus to crimp celluloseand cellulose ester yarns, including heating same while twisting, but sofar as I am aware no apparatus for this purpose has come into practicalcommercial use. So far as I know no commercial apparatus has heretoforebeen devised to treat a traveling linear synthetic organic polymer yarnunder controlled tension prior to winding up. In addition, in thedevices as heretofore proposed only a single yarn is treated and noproposal has been made to crimp simultaneously a series of yarns or topass a single yarn, or several yarns, through such apparatus at speedsof the order of -40 meters per minute.

The principal object of the invention, accordingly, is to provide asimple, efficient apparatus of the kind described which shall be capableof treating such linear synthetic organic polymer yarn at such speedsunder the conditions mentioned to produce a high-quality crirnped yarn.

It will be understood that in producing permanently crimped nylon yarnit is necessary to control within predetermined critical limits certainfunctions, such as the rate of linear feed of the yarn, conditions andlength of time of the setting operation, rotative speed of the twister,tension, etc. Therefore, in order to increase production, it is not onlynecessary to treat alarge number of yarns simultaneously and to giveeach yarn individual treatment, but to provide apparatus which withcertainty will produce exactly the same results on the individual yarnsbeing treated.

it is another object of this invention to provide apparatus adapted totreat a multiplicity of yarns simultaneously and uniformly.

It is a further object of this invention to provide improved means forsteaming the yarn under pressure during the twisting operation andduring an appreciable part of the twisting path.

Further and other objects, features and advantages of the invention willmore clearly appear from thedetailed description given below, taken inconjunction with the accompanying drawings illustrating, by way ofexample, presently preferred embodiments of the invention, and in which:

Fig. l is an end elevation of anembodim'ent of the invention as viewedfrom the drive end with certain parts shown in section and otherssomewhat schematically;

Fig. 2 is a plan view of the apparatus shown in Fig. l with certainparts omitted for clarity;

Fig. 3 is a sectional view taken at 3-3 of Fig. 2 showing furtherdetails of the steaming tube and its pressure seals; I

Fig. 4 is a sectional view taken at line -4-4 of Fig. 2;

Fig. 5 is a somewhat diagrammatic view' showing the operative andcontrol circuits;

"ice

Fig. 6 is a somewhat diagrammatic view showing further details of thetwister motor controls;

Fig. 7 is a similar view showing further controls for said motors;

Fig. 8 is a sectional view taken at 8-8 of Fig. 2; and

Fig. 9 is a side elevation, partly in section, showing a suitabletwister unit.

Referring more particularly to Figs. 1 and 2, the apparatus is providedwith a unitary frame designated in general as 1, on which is mounted aseries of twisting devices (in the present embodiment, fifty in number)for handling simultaneously a like number of yarns. Said devices areindividually designated in general (Fig. 2) as TD-1, TD-Z, TD-3 TD-50.These devices are arranged in parallel in plan view and at the samevertical level so that in end elevation only the first device TD-l isseen (Fig. 1) together with certain parts and mechanisms common to allthe devices.

Referring to Fig. 1, each of the individual yarn twisting devices, suchas TD1 ZED-50 is constructed and arranged and the several devicesinterrelated as follows:

Each said device has a support such as 2 secured to the frame 1 forcarrying a yarn feeding bobbin, such as 3 to supply a yarn such as Y toyarn guides and brake unit such as 4, through which the yarn passes to aguide such as 5 (Fig. 1) mounted for lateral reciprocation on the upperportion of frame 1, individual guides 5 for the respective devices beingpreferably mounted on a common reciprocating'bar. The construction andoperation of such guides 5 are conventional and well known to thoseskilled in the art. Each device also has a first pair of conveyingrollers such as feed rollers 6-7 mounted to receive the yarn passingthrough the corresponding guide 5, the roller 7 being the power rollerand, in the present embodiment, being common to all of the twistingdevices. On the opposite or output side of the machine a second pair ofconveying rollers such as the draw rollers 8-9 is provided for each saiddevice TD1, etc., the roller 9 being the power roller and, in thepresent embodiment, being common to all of said twisting devices. In thealternative, separate roilers 7 and 9 could be used for the respectivetwisting devices and the series of rollers 7 and 9 could be mounted oncommon drive shafts respectively; the important thing being that theseries of rollers '7 and the series of rollers 9 each be driven from acommon source respectively. The power roller 7 has secured to one endthereof a sprocket wheel 10 (see also Fig. 2) in driven engagement witha chain 11 driven from a sprocket 12 on the output shaft of a variablespeed transmission such as the device 33, which receives power through achain drive 14 connected to the output side of a variable speedtransmission such as the device 15, which in turn has its input sideconnected by a chain 16 to a source of power such as the electricalmotor 17. The power roller 9 carries a tached to its corresponding end asprocket wheel 13 driven by chain 19 (Fig. 2) from the sprocket 29,which is con nected through chain 21 to sprocket 22 and thence by chain14 to the output side of the transmission 15. As will be seen from Figs.1 and 2, the chain 21 drives a variable speed transmission such as thedevice 23 whose output is reversely connected to the drive chain belt24, which through the intermediary of pulley 25 and-chain belt 26,serves to drive a winding drive roller 27 common to all of the twistingdevices and forming a part of the takeup device associated respectivelywith said twisting devices. The variable speed transmission devices 13,15 and 23 may be the P. I. V. (Link Belt Co., Chicago, Illinois) orReeves (Reeves Pulley (30., Columbus, Indiana). 7 p t Each said takeu'pdevice comprises supportingmeans for a cross wound bobbin such as 28whereby the bobbins may be individually moved into or out of'operativee11- gagement with the roller 27; and which talzeup device alsocomprises a traverse guide such as 29 through which the yarn passes tothe bobbin 23 and an adjustable tensioning device comprising a roller 3%around which yarn passes from the draw rollers 89. Such talreupmechanism is conventional and well understood to those skilled in theart.

It will be understood from the foregoing that the first conveyor rollers6-7 for all of the twisting devices TD1 TD--50 are driven in synchronismfrom a common source, as also are the second pair of conveyor rollers8-9 and the takeup devices 2728. Furthermore, speed of the firstconveyor rollers 6---7 speed of the second conveyor rollers 8 9 ablerelative to each other and the speed of the ta cup devices 2728 isadjustable, so that by proper n lation of the variable speed units, thedegree of tension. to be imposed upon the yarns, the linear yarn feedand the takeup feed for all. of the twisting devices may besimultaneously varied and the several yarns subjected to equalconditions. After the relative adjustments are made the over-all speedof the machine may be adjusted by the device the yarn preferably beingfed through the tubes 31 at a speed of 40 meters per minute.

Referring to Figs. 1 and 2: Each of the TD-1 TD devices comprises aplasticizing chamber which, in the present embodiment, takes thepreferred form of a steam pressure tube 31 rigidly secured (Fig. 3) atits opposite open ends in blocks 32-33, which are rigidly secured to theframe 1. The tube 31 is provided at its respectively opposite ends withlabyrinth seals 34-35 which are readily detachable from said tube 31 asby being in screw threaded engagement in the blocks 32 and 33, for thepurposes to be hereinafter mentioned. Each of the labyrinth sealscomprises a hollow chamber such as 36 provided at its inner ends with aninternal flange such as 37 and at its outer end with a screw threadedplug such as 38. Within the chamber provided in 36 are disposed aplurality of diaphragm members 39 spaced apart axially of the chamberand extending in a direction transverse thereof so as to provide aplurality of chambers 40 which are one less in number than the number ofdiaphragms. The diaphragm members 39 and the plug 38 are provided withaxially aligned orifices such as 41 which are preferably 0.6 millimetersdiameter. It will thus be seen that the labyrinth seals provide at eachend of the tube 31 a plurality of chamhere such as 40 in which the steampressure is gradually and successively reduced from the interior of thetube 31 towards the chambers 40 of the labyrinth seal situated mostdistant from the ends of the tube 31, i. e., as the yarn passes into theinput end at the left and out of the output end of the right. The tube31 is provided with an inlet port 33 for the entrance of steam and anoutlet port 32' for the passage of condensate. As will be seen in Fig. 1the tubes 31 are inclined upwardly from their input toward their outputends, preferably at an angle of from 2l0, to facilitate the drainage ofcondensate out of the ports 32'. Such condensate as may slowlyaccumulate in the bottom of the labyrinth seal chambers 40 may beremoved when the machine is not in operation, by taking the seals apart,which may be readily done by the construction hereinafter pointed out.However, the removal of such condensate is required only at very longintervals of operation. Adjacent the input end of the seals 34 there isprovided a common exhaust conduit 42 (Figs. 1 and 8) provided withopenings in its opposite sides in axial alignment with the orifices 41for the passage therethrough of yarns such as Y. To facilitate thethreading of yarns, this conduit is spaced from the ends of the seals 34and is connected thereto by adjustable sleeves such as 43 telescopicallydisposed extcriorly of the labyrinth chambers such as 36. Similarly theopposite or output labyrinth seals are provided with a common exhaustconduit 44 (Figs. 1 and 4) provided with axially aligned openings forthe passage of yarns such as Y and similarly spaced from the ends of thelabyrinth seals which are similarly provided with telescopic sleevessuch as 45. It is noted that the width of the conduit 44 in thedirection of yarn travel is quite narrow at the level of the yarn andincreases in cross section below the uppermost frame member. The reasonfor this will be apparent hereinafter. The conduits 42 and 44 are incommunication through branches 46 and 47 with an exhaust suction pipe 48connected with a suitable exhaust fan assembly 49. The relatively narrowwidth of the header 44 (Figs. 1 and 4) at the yarn level makes possiblean increased cooling zone without the expensive widening of the entiremachine.

Each of the TD1 TD-50 units is provided with a twister such as 50 (Figs.1 and 4). These twisters each comprise a hollow rotatable shaft 51through which the yarns such as Y may be axially fed and at its outputend the hollow shaft is provided with a twister element 52. Theparticular twister which we have found to be exceptionally suitable forthis purpose is that described and claimed in co-pending applicationSerial No. 407,725, filed February 2, 1954. These twisters 50 (Figs. l,2 and 4) comprise a three-phase electric motor and are provided withcompressed air bearings, the electrical and compressed air circuits andcontrols for which will be described hereinafter. Since these motorsoperate at very high rotative speeds (up to 200,000 R. P. M. orgreater), they are securely mounted in heavy housings such as 53 (Fig.4) provided with a removable hood portion 54 to facilitate threading theyarn.

Further structural details of the twister units 50 will now bedescribed.

Referring more particularly to Fig. 9, the twister shaft is designatedas 101 and is supplied with suitable motive means to drive the same at ahigh speed of the order of 330,000-150,000 R. P. M. and higher. In thepresent embodiment this motive means consists of an electric motordesignated in general as 102 having a rotor 103 carried by the shaft 101and a stator fixed to the housing of the motor 102 and consisting of anelectrical winding 104 and a core 105. The shaft 101 is provided withend plates 106 and 106 which rotate with said shaft. The housing ofmotor 102 is provided with hearing blocks 107 and 107 disposed adjacentsaid end plates 106106 in which are provided suitable compressed airberaings. In general, such bearings may be. constructed and arranged ina manner now to be described. The bearing blocks are provided with axialbores in alignment with the shaft 101 and each of which has rigidlysecured therein, as by a press fit, a bearing sleeve such as 108 whoseinternal diameter is sufficiently larger than the external diameter ofthe shaft 101 so as to function in the manner to be hereinafterdescribed. For example, the difference between the internal diameter ofthe sleeve 108 and external diameter of the shaft 101 may be of theorder of 0.01-0.03 millimeter and will depend upon the degree of airpressure employed. The sleeves such as 108 are each provided with aplurality of relatively small holes such as 109 disposed peripherallythereabout and in communication with a series of annular channels 110interconnected by a common passage such as 111 in communication with thebore 112 adapted to receive air under pressure from a suitable sourceconnected to the tube such as 113. The air pressure should be of theorder of two atmospheres and preferably greater.

The clearance between the shaft 101 and the bearing sleeve 108 is suchthat the shaft is supported free of contacts with the walls of thesleeves by means of the compressed air and the compressed air passingoutwardly passes through cavities such as 114 found on the inner facesof the plates 106 and 106 and outwardly through the space between theend plates 10610,6' and the bearing blocks 107 and 107. The clearancebetween end plates 106 and 106' and the respective portions of thebearing blocks 107 and 107' is such that said blocks are held out ofcontact with said plates by said compressed air.

The shaft 101 is provided with an axial bore 115 extending therethroughfrom the input or right hand end thereof to the output or left hand endthereof for the passage of yarn traveling in a path along an axis yy oflinear feed. The bore 115 at the output end of the shaft and immediatelyadjacent thereto is provided with a throat 116 of reduced diameterextending for a limited axial distance. in the present embodiment, forconveniences of construction, the output end of the shaft is providedwith a sleeve portion 101a rigidly secured thereto and forming a partthereof. The twisting loop 117 is secured to the end 101a of said shaft.

From the foregoing it will be understood that each of the sub-assembliesof TD-l TD-5li comprises the various parts above referred to arranged inaxial alignment so that the respective yarns passing therethrough may befed along a straight linear feed axis. The telescopic conduit branchessuch as 43 and 45 (Figs. 1 and 3) and the removable labyrinth seals 34and 35 and the removable twister hoods 54 all facilitate threading theyarn.

The length of the tubes 31 is preferably 1 meter and the length of eachof the labyrinth seals is of the order of 7 centimeters. The distancefrom the output ends of the seals 35 to the input of the twister head ispreferably at least 5 centimeters to permit a suitable cooling zonebetween the 'plasticizing chamber and the twister. The steam tubes 31are adapted to withstand and maintain relatively high steam pressures ofat least one atmosphere and up to five atmospheres or greater.

Referring more particularly to Fig. 5, the motors of the twisters 50(schematically shown) are three-phase motors with short circuit rotorand are supplied by a three-phase medium frequency generator 55 over acircuit net 56. The entire net is under control of a switch 57 and eachmotor is under individual control of a separate switch such as 58. Theair bearings of the respective twisters 50 are supplied with pressureair through individual branch lines 59 connected to a common manifold 60which in turn is connected by a common line 61 to a suitable source ofpressure air designated 62. The line 61 is provided with a stopcock 63,a pressure gauge 64, a filter 65, and a reduction valve 66. A pressurerelay 67 is connected to the line 61, intermediate the reduction valve66 and manifold 60, by means of a line 68 provided with a pressure gauge69. The pressure relay 67 actuates the switch 57 and is constructed sothat when the pressure in the line 61 falls below the predeterminedpressure the relay 67 opens the switch 57 to disconnect the twisters 50.In this way the twisters are protected against damage in the event thatthe pressure supplied to the bearings falls below the minimum requiredto safely support the twister shaft 51 (Fig. 4).

It is further important that no pressure air should be supplied to themotors when the motors are cold, since condensation of moisture couldtake place from the compressed air with the resultant danger ofcorrosion. To prevent this the following provision is made: A suit--able air valve 70 (Fig. 6) is disposed in the branch lines 59 of eachtwister 50 and is held in closed position when the switch 58 is open, asshown in Fig. 6. This valve is suitably clutched to the switch 58 soasto normally lock the switch 53 in open position when the air valve isclosed. Provision is made for opening the air valve 70, as by pressingthe pin 58', which automatically unlocks the switch 58 for operation.

In Fig. 7 an alternative means is illustrated for preventing moisturecondensation. In this embodiment the following provision is made forheating the twisters 56 when the electrical motor is not operating torotate the shaft 51. A changeover switch 71 .is built in the currentsupply line to the motor of each twister 50 which connects the motorwith either the medium frequency net 56, for rotation of the motor, orconnects two phases of the motor winding with a regular alternatingcurrent line 72 to thereby supply heat to the motor while it is notoperating to rotate the shaft.

The supply of steam for the steam pressure tubes 31 is provided from acommon supply line 73 and interconnected to individual steam tubes bybranch lines such as 74 (connected to the inlet ports such as 33' ofFig. 3) and provided with valves such as 75, and the main line '73 isprovided with a main valve 76 and with a pressure gauge '77. The exactpressure desired is obtained by a suitable pressure control valvedesignated as 78. The line is suitably provided with a condensation pot79 having the usual condensation drain connection.

The tubes Eli are preferably inclined at an angle of not less than 2 tomake it possible for the condensation water produced in the tube to bedrained off unhindered through individual drain lines such as 80,connected at one end to the outlet ports 32 (Fig. 3). The lines 80 aresupplied with individual valves 81 and their other ends are connected toa common manifold 82 which is connected to a suitable condensation pot83 having the usual drain line. The steam tubes 31 may, of course, belevel, out this will make it more difiicult to remove the condensate.

Having thus described my invention with particularity with reference topresently preferred embodiments thereof, it will be obvious to thoseskilled in the art, after understanding my invention, that variouschanges and modifications may be made therein without departing from thespirit and scope of my invention, and I aim in the appended claims tocover such changes and modifications as fall within the scope of theinvention.

What I claim is:

I. In apparatus for permanently crimping synthetic filament yarn, thecombination of a series of false twisting devices each comprising yarnsupply means, a first yarn conveying device for receiving yarn from saidsupply means, a device for steaming yarn under pressure of at least oneatmosphere, a motor operable at high rotative speed and having a hollowshaft with a twister attached at one end, a second yarn conveyingdevice, and a yarn takeup device, said first and second conveyingdevices, steaming device, hollow twister shaft and attached twisterbeing arranged in alignment for the linear feed of said yarn in astraight line, and common means for operating said series of falsetwisting devices.

2. Apparatus as set forth in claim 1 in which individual short steamconduits are operatively connected to said pressure steaming devices ofsaid series of false twisting devices respectively, and said shortconduits are opei tively connected to a common supply line which isprovided with pressure control means, whereby steam pressure may besimultaneously uniformly controlled in all of said pressure devices.

3. Apparatus for the production of crimped synthetic filament yarnswhich comprises a steaming tube, provided at its input and output endsrespectively with labyrinth seals each having a multiplicity of axiallyspaced partitions provided with nozzle-shaped passageways in alignmentfor the passage of arn therethrough, the passageways being of the orderof 0.6 millimeters diametcr, to thereby permit a steam pressure of atleast one atmosphere in said steaming tube.

4. Apparatus as set forth in claim 3 in which the steaming tube isinclined upwardly from its input end to its output end at an angle of atleast 2.

5. Apparatus as set forth in claim 3, in which each labyrinth sealconsists of a hollow chamber detachably secured to the respective end ofsaid steaming tube and provided with a plurality of diaphragm membersdisposed within said hollow chamber extending in a direc ave ees tiontransverse its axis and spaced apart axially, said diaphragms havingaxially aligned orifices to jointly provide aligned entrance and exitpassageways for said steaming tube, to thereby provide a plurality ofchambers in which the steam pressure is gradually reduced from theinterior of said steaming tube toward the chambers of the labyrinthseals situated most distant from the ends of said steaming tube.

6. Apparatus as set forth in claim 3 wherein each labyrinth sealconsists of a hollow chamber detachably secured to the adjacent end ofsaid steaming tube and provided with a number N of diaphragm membersdisposed within said hollow chamber extending in a direction transverseits axis and spaced apart axially, said diaphragms having axiallyaligned orifices to jointly provide aligned entrance and exitpassageways for said steaming tube, to thereby provide in each labyrinthseal N-1 of chambers in which the steam pressure is gradually reducedfrom the interior of said steaming tube toward the chambers of thelabyrinth seals situated most distant from the ends of said steamingtube.

7. Apparatus as set forth in claim 3 in which each labyrinth sealconsists of an elongated chamber detachably secured at one end to therespectively adjacent end of said steaming tube, said chamber beingprovided at one end with an internal seat, a plurality of diaphragmmembers disposed within said chamber extending in a direction transverseits axis and spaced apart axially, a removable retaining member disposedin the opposite end of said chamber for holding said diaphragms therein.against said internal seat and provided with a central opening for thepassage of yarn therethrough, said diaphragms having axially alignedorifices jointly providing a passageway through said labyrinth seal, tothereby provide at the entrance and exit of said steaming tube aplurality of chambers in which steam pressure is gradually reduced fromthe interior of said steaming tube toward the chambers of the labyrinthseals situated most distant from the ends of said steaming tube.

8. In apparatus for permanently crimping yarn, the combination of aseries of false twisting devices each comprising a first yarn conveyingdevice for receiving yarn from a suitable source of supply, a yarnplasticizing chamber, an electric motor operable at high rotative speedand having a hollow shaft journaled in compressed air bearings andprovided with a twister, a second yarn conveying device, and a yarntakeup device, said conveying devices, yarn plasticizing chamber, hollowtwister shaft and attached twister being arranged in alignment for thelinear feed of said yarn in a straight line, a common electrical powerline connected to said series of motors, a common compressed air supplyline con nected to the compressed air bearings of said series of motors,an electrical switch controlling said electrical power line, anair-pressure actuator for said switch and in communication with said airsupply line and adapted to actuate said switch to open position when thepressure in said air supply line drops below a predetermined u minimumpressure, to thereby stop the operation of said motors when thecompressed air supplied to said bearings is insuflicient operatively tosupport said shafts.

9. In apparatus for permanently crimping yarn, the combination of aseries of false twisting devices each comprising a first yarn conveyingdevice for receiving yarn from a suitable source of supply, a yarnplasticizing chamber, an electric motor operable at high rotative speedand having a hollow shaft journaled in compressed air hearings andprovided with a twister, a second yarn conveying device, and a yarntakeup device, said conveying devices, yarn plasticizing chamber, hollowtwister shaft and attached twister being arranged in alignment for thelinear feed of said yarn in a straight line, a common source of powerfor said first and second conveying devices and said yarn takeup devicesof said series of yarn-twisting devices, three drive shafts drivinglyconnected to said series of first conveyor devices and said series ofsecond conveyor devices and said series of yarn-takeup devicesrespectively, and variable speed transmissions connected to said commonsource of power and said three shafts and adapted to vary the speed ofsaid three drive shafts individually and collectively.

10. in apparatus for permanently crimping yarn, the combination of aseries of false twisting devices each comprising a yarn plasticizingchamber, an electric motor operable at high rotative speed and having ahollow shaft iournaled in compressed air bearings and provided with atwister and yarn conveying and tensioning means for receiving yarn froma suitable source of supply and moving the same through said chamber andhollow shaft and twister at a predetermined tension, said yarn conveyingand tensioning means, yarn plasticizing chamber, hollow twister shaftand attached twister being arranged in alignment for the linear feed ofsaid yarn in a straight line, a common electrical power line connectedto said series of motors, a common compressed air supply line connectedto the compressed air bearings of said series of motors, an electricalswitch controlling said electrical power line, an air-pressure actuatorfor said switch and in communication with said air supply line andadapted to actuate said switch to open position when the pressure insaid air supply line drops below a predetermined minimum pressure, tothereby stop the operation of said motors when the compressed airsupplied to said bearings is insufiicient operatively to support saidshafts.

References Cited in the file of this patent UNITED STATES PATENTS2,089,199 Finlayson et al Aug. 10, 1937 2,111,209 Dreyfus Mar. 15, 19382,244,832 Finlayson et al. June 10, 1941 2,398,856 Reel Apr. 23, 19462,463,620 Heberlein Mar. 8, 1949 2,475,922 Stockly July 12, 19492,575,781 Barach Nov. 20, 1951 2,622,961 Finlayson et a1. Dec. 23, 1952

